Dutasteride and Tamsulosin (Oral)

Dutasteride and tamsulosin, known in the US under the brand name Jalyn, is a combination treatment for enlarged prostate which is administered orally.


Dutasteride and tamsulosin is a combination oral medicine used to treat the symptoms of enlarged prostate in men. Enlarged prostate, also known as benign prostatic hyperplasia (BHP) is a relatively common problem which can occur as men get older.

Although not life-threatening, the condition can cause a variety of problems related to urination. This is because as the prostate become larger, certain muscles within it get in the way of the tube through which urine flows from the bladder. Common symptoms include an urge to urinate more frequently, a weak stream during urination, and a sensation of being unable to completely empty the bladder.

One of the reasons for enlarged prostate is an enzyme called 5-alpha-reductase, which causes testosterone to change into another hormone that forces the prostate to grow in size. Dutasteride blocks the action of the 5-alpha-reductase enzyme in order to reduce the size of the prostate. The drug is only effective for as long as it is taken, so patients can expect to take dutasteride and tamsulosin on a long-term basis.

Tamsulosin is an alpha-adrenoceptor blocker and it works to relax muscles in the prostate gland and the opening of the bladder. This helps to increase urine flow and reduce the severity of symptoms associated with enlarged prostate.

In the US, dutasteride and tamsulosin is only available with a doctor's prescription. It is an oral medication administered in capsule form, and in the US its brand name is Jalyn. The drug should not be handled by pregnant women or women who plan to become pregnant because dutasteride is known to cause birth defects in male fetuses.

Conditions Treated?

  • Benign prostatic hyperplasia

Type Of Medicine?

  • Enzyme 5-alpha-reductase inhibitor (dutasteride)
  • Alpha-adrenoceptor blocker (tamsulosin)

Side Effects

Dutasteride and tamsulosin can cause unwanted effects alongside its needed effects. Not all of these side effects will occur, but if they do they may require medical attention.

If you notice any of the following side effects, check with your doctor as soon as possible or visit the ER if your doctor is not available:

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    • More common:

O Chills
O Cold sweats
O Dizziness, faintness or lightheadedness when getting up from sitting or lying positions
O Confusion

    • Less common:

O Fever
O Difficult or painful urination
O Lower back or side pain
O Chest pain
O Cough or hoarseness

    • Incidence unknown:

O Peeling, blistering or flaking of the skin
O Large, hive-like swellings on the face, eyelids, lips, tongue, throat, hands, legs, feet or genitals
O Pain or swelling of the skin
O Sweating
O Prolonged or painful erection of penis
O Blurred vision
O Difficult breathing
O Shortness of breath
O Fast, pounding, racing or irregular heartbeat
O Abnormal tiredness or weakness

Some side effects associated with dutasteride and tamsulosin are minor and don't require medical attention. However, if they become particularly severe or prolonged, you could mention them to your doctor. Often, minor side effects dissipate once the body adjusts to the medicine. If any of the following side effects become very bothersome, consult your doctor:

    • More common:

O Changes in semen or discharge of semen
O Reduced sex drive
O Reduced sexual performance
O Inability to achieve or maintain an erection
O Enlarged or painful breast tissue
O Dizziness

    • Less common

O Back pain
O Aches and pains throughout the body
O Headache
O Pain or tenderness around cheekbones or eyes
O Congestion or stuffy nose
O Runny nose
O Sneezing
O Dry or sore throat
O Cough
O Tender, swollen glands in neck
O Diarrhea
O Loss or lack of strength
O Sleepiness or drowsiness
O Difficulty sleeping
O Unable to sleep
O Mild shortness of breath or troubled breathing
O Tightness of chest or wheezing
O Changes in voice

    • Incidence unknown:

O Hives or welts
O Itching
O Redness of skin
O Skin rash
O Vomiting
O Constipation

This is not necessarily an exhaustive list of all side effects which could occur during treatment with dutasteride and tamsulosin. If you notice any other side effects not listed here, consult your doctor as soon as possible. You could also report new side effects to the FDA, or your doctor could do this for you.


The recommended dose of dutasteride and tamsulosin for adult men is 0.5 mg dutasteride and 0.4 mg tamsulosin taken once each day. The correct doses of the drug are combined into capsules so that patients can simply take one capsule daily.

It is best to take dutasteride and tamsulosin at around the same time each day, 30 minutes after eating. Patients are usually advised to choose a meal after which to take the capsule, and take it after the same meal every day. The capsule should be swallowed whole with a little water if necessary. It should not be broken, crushed, chewed or opened.

If you miss a dose of dutasteride and tamsulosin, simply take the missed dose as soon as you remember, as long as it is on the same day. If you remember the missed dose on the following day, simply skip the missed dose and continue with your normal dosing schedule. Do not take more than one dutasteride and tamsulosin capsule at a time, as doing so could increase the risk of harmful side effects.

Do not stop taking dutasteride and tamsulosin even after you begin to feel better and experience fewer symptoms of enlarged prostate. Dutasteride only reduces prostate size for as long as you take it for. If you stop taking the medicine, the prostate will simply grow back to its enlarged size. Only stop taking dutasteride and tamsulosin if your doctor advises you to do so.


Dutasteride and tamsulosin can interact with a wide range of medicines. Some interactions should be completely avoided, while others may be tolerated if all drugs are absolutely necessary. Make sure your doctor knows about all the medicines you currently take in order that they can assess the risk of interactions. You should tell them about your prescribed medicines as well as those purchased over the counter, including herbal supplements and multivitamins. It may be helpful to keep a list of all medicines you take which you can present to each doctor, pharmacist or other healthcare professional that you see.

It is particularly important to tell your doctor if you are taking the following types of medicine:

  • Antidepressants
  • Beta-blockers
  • Medicines for HIV
  • Medicines for viral infections

Boceprevir (brand name Victrelis) is an antiviral medicine which should never be taken at the same time as dutasteride and tamsulosin. Your doctor will either choose not to treat you with dutasteride and tamsulosin if you are already taking boceprevir, or they may change boceprevir for an alternative medicine.

The following medicines are not recommended for use at the same time as dutasteride and tamsulosin. However, in some instances, both medicines may be necessary. If your doctor can't change the medicines you already take, they may change the dosages of your existing medicines or instruct you to take them at certain times of day to minimize the risk of harmful interactions. Always follow your doctor's instructions closely.

  • Atazanavir (Reyataz)
  • Ceritinib (Zykadia)
  • Clarithromycin (Biaxin, Biaxin XL, Biaxin XL-Pak)
  • Cobicistat (Tybost)
  • Conivaptan (Vaprisol)
  • Idelalisib (Zydelig)
  • Indinavir (Crixivan)
  • Itraconazole (Onmel, Sporanox, Sporanox PulsePak)
  • Ketoconazole (Nizoral)
  • Lopinavir (Kaletra)
  • Nefazodone (Serzone)
  • Nelfinavir (Viracept)
  • Paroxetine (Brisdelle, Paxil, Paxil CR, Pexeva)
  • Posaconazole (Noxafil)
  • Ritonavir (Norvir, Norvir Soft Gelatin, Kaletra)
  • Saquinavir (Invirase, Fortovase)
  • Tadalafil (Adcirca, Cialis)
  • Telaprevir (Incivek)
  • Telithromycin (Ketek, Ketek Pak)
  • Voriconazole (VFEND)

The following medicines are not recommended for use with dutasteride and tamsulosin because they can increase the risk of certain side effects. However, if both drugs are necessary, your doctor may continue to prescribe both with adjustments to dosages or times at which you take the medicines. Always follow your doctor's instructions closely to minimize the risk of harmful side effects.

  • Acebutolol (Sectral)
  • Alprenolol
  • Atenolol (Tenormin)
  • Avanafil (Stendra)
  • Betaxolol (Kerlone)
  • Bevantolol
  • Bisoprolol (Zebeta)
  • Bucindolol (Gencaro)
  • Carteolol (Ocupress)
  • Carvedilol (Coreg, Coreg CR)
  • Celiprolol
  • Cimetidine (Tagamet, Tagamet HB)
  • Ciprofloxacin (Cipro, Cipro XR, Proquin XR)
  • Dilevalol
  • Diltiazem (Cardizem, Cartia XT, Dilacor XR, Dilt-CD, Diltia XT, Dilt-XR, Diltzac, Matzim LA, Taztia XT, Tiazac)
  • Esmolol (Brevibloc)
  • Ketoconazole (Nizoral)
  • Labetalol (Trandate, Normodyne)
  • Levobunolol (Akbeta, Betagan, Levobunolol, Betagan C-Cap)
  • Mepindolol
  • Metipranolol (OptiPranolol)
  • Metoprolol (Lopressor, Metoprolol Succinate ER, Metoprolol Tartrate, Toprol-XL)
  • Nadolol (Corgard)
  • Nebivolol (Bystolic)
  • Oxprenolol
  • Penbutolol (Levatol)
  • Pindolol (Visken)
  • Propranolol (Hemangeol, Inderal LA, Inderal XL, InnoPran XL, Inderal)
  • Ritonavir (Norvir, Norvir Soft Gelatin)
  • Sildenafil (Revatio, Viagra)
  • Sotalol (Betapace, Sorine, Sotylize)
  • Talinolol
  • Tertatolol
  • Timolol
  • Vardenafil (Levitra, Staxyn)
  • Verapamil (Calan, Calan SR, Isoptin SR, Verelan, Verelan PM, Isoptin, Isoptin I.V., Covera-HS)



If you have an allergic reaction to dutasteride and tamsulosin in the past, or to drugs similar to dutasteride and tamsulosin, or to any of the ingredients in dutasteride and tamsulosin capsules, you may not be able to take it. Tell your doctor about all the allergies you suffer from, including those to animals, pollens, chemicals, foods and dyes.

Patients with an allergy to sulfa drugs are at a higher risk of allergic reaction to dutasteride and tamsulosin. Make sure your doctor knows if you have had a reaction to sulfa drugs such as:

  • Sulfamethoxazole
  • Sulfasoxazole
  • Sulfasalazine
  • Septra
  • Bactrim
  • Azulfidine

If you notice any of the following symptoms of allergic reaction while taking dutasteride and tamsulosin, consult your doctor as soon as possible:

  • Rash
  • Itching
  • Hives
  • Chest tightness
  • Labored breathing
  • Swollen face, eyelids, lips, tongue or throat

Pediatric use

Dutasteride and tamsulosin is not recommended for use in children. The safety and efficacy of the drug have not been established in the pediatric population.


Dutasteride and tamsulosin is suitable only for adult men, since it treats enlarged prostate. However, it is very important that pregnant women, or women who plan to become pregnant, do not consume or touch dutasteride and tamsulosin. This is because dutasteride has been proven to cause fetal abnormalities and birth defects in male fetuses. Similarly, dutasteride and tamsulosin could pose harmful effects to nursing infants if consumed or touched by breastfeeding women.

If you do touch dutasteride and tamsulosin capsules while pregnant, planning to become pregnant, or breastfeeding, wash hands with warm, soapy water immediately and talk to your doctor as soon as possible.

Patients with liver disease

In patients with reduced liver function, dutasteride and tamsulosin will be removed at a much slower rate from the body than in those with normal liver function. This can increase the potency of the drug and could lead to harmful or severe side effects. For this reason, dutasteride and tamsulosin is used with caution in patients with liver disease.

Risk of worsening medical conditions

Dutasteride and tamsulosin can make the following medical conditions worse:

  • Hypotension (low blood pressure)
  • Postural hypotension (low blood pressure when getting up from sitting or lying positions)
  • Priapism (prolonged or painful erection)

If you have any of these conditions or have a history of them, you may not be able to take dutasteride and tamsulosin. Make sure your doctor knows about your full medical history so that they can assess whether the drug is safe for you. They may choose an alternative treatment for enlarged prostate, or they may monitor you more closely when you first start taking dutasteride and tamsulosin.


Dutasteride and tamsulosin may cause drowsiness, particularly when a patient first begins taking it. Avoid driving or operating machinery when you first start taking this medicine until you know how it affects you. Alcohol may worsen drowsiness, so you may need to avoid alcoholic beverages while taking dutasteride and tamsulosin.


Dutasteride and tamsulosin capsules should be stored in the container they were provided in. Store the medicine at room temperature and away from direct light, heat and moisture. Keep them from freezing. Do not store the drugs in the bathroom as the heat and humidity could damage them.

Keep dutasteride and tamsulosin well away from children and pets. Ensure the caps of the container are tightly closed at all times, and store the container up and away from the ground so that it is not within easy reach.

Dispose of unused or expired dutasteride and tamsulosin capsules according to your healthcare provider's instructions. There may be a local medicine take-back program that you could use to ensure the medicine is safely disposed of.


Dutasteride and tamsulosin is a combination medicine designed to treat benign prostatic hyperplasia (BHP), also known as enlarged prostate. Dutasteride works to block an enzyme responsible for hormone changes which lead to enlarged prostate, thus reducing the size of the prostate. Meanwhile, tamsulosin relaxes muscles in the prostate and the opening of the bladder to relieve symptoms of enlarged prostate, such as slow urine flow, increased urge to urinate and incomplete emptying of the bladder.

The recommended dose of dutasteride and tamsulosin is one capsule taken once each day. The capsule should be taken 30 minutes after eating at the same time every day. It's important to keep taking the medicine even after you feel better, because the effects of dutasteride will stop as soon as you stop taking it and the prostate will begin to grow to a large size once again.

Dutasteride and tamsulosin is designed only for adult males. It should not be consumed or even touched by women who are pregnant or plan to become pregnant, because it can cause serious birth defects in male fetuses. It should also be avoided by breastfeeding women due to the risk of harm to nursing infants. Women who do touch dutasteride and tamsulosin capsules should wash their hands immediately and consult their doctor.

Sometimes dutasteride and tamsulosin can cause drowsiness, dizziness, and problems with sexual performance. These side effects are usually nothing to worry about unless they become severe or prolonged. If you experience breathing problems, pounding heart rate, or problems with urination while taking dutasteride and tamsulosin, consult your doctor immediately.